A distinction is often made between frogs and toads on the basis of their appearance, prompted by the convergent adaptation among so-called toads to dry environments, which often entails a brown skin for camouflage.

Salamanders and newts are amphibians with long, slender bodies, short legs, and long tails. Although they resemble lizards, they are true amphibians, and have soft, moist skin that, for many species, means a life spent close to water.

Salamander is the common name applied to approximately 500 amphibian vertebrates with slender bodies, short legs, and long tails. Salamanders superficially resemble lizards, but are easily distinguished by their lack of scales.

The poison dart frog, poison arrow frog, dart frog or poison frog, is the common name given to the group of frogs belonging to the family Dendrobatidae. Poison dart frogs are native to two geographical regions: Central America and South America.

Newts are small, usually bright-coloured semiaquatic salamanders of North America, Europe and North Asia, distinguished from other salamanders by the lack of rib or costal grooves along the sides of the body.

Frogs and toads are species of tailless amphibians, with short, squad front legs and muscular hind legs adapted for hopping or leaping. Their life cycle includes a "tadpole" phase, in which they appear almost fish-like right out of the egg.

The American Bull Frog uses its skin, Buccal Cavity, and lungs for respiration. Cutaneous ("skin") gas exchange is very important in all amphibians. The American Bull Frog (Rana catesbeiana) is an aquatic frog, a member of the family Ranidae.